The present invention relates to system and methods for composing images for magnetic resonance angiography.
Magnetic Resonance (MR) Angiography (MRA) is a technique to image vasculature in a human body. During data acquisition, a set of volumes covering the whole body or peripheral vessels is obtained. One issue that needs to be addressed is the problem of aligning (registering) these volumes to produce a single compact image.
MRA has developed as a way of generating a predictable image contrast due to the nature of a blood flow. A contrast agent is usually applied prior to the imaging to enhance the visibility of vascular structures. MRA enables a physician to perform a complete range of body vasculature examinations. See, for example, V. M. Runge, J. Kirsch, and C. Lee, Contrast-enhanced MR angiography, Journal of Magnetic Resonance Imaging, (3):233-239, 1993; H. H. Schild and C. K. Kuhl, Contrast-enhanced magnetic resonance angiography, potential applications and pitfalls in magnetic resonance angiography-guided therapy: a review, Investigative Radiology, 9(9):524-527, 1998 and Anil N. Shetty, Kostaki G. Bis, and Ali Shirkhoda, Body vascular MR angiography: Using 2d- and 3d-time-of-flight techniques, Concepts in Magnetic Resonance, 12(4):230-255, 2000. This includes the diagnosis of circulatory diseases in diabetics and other patients. See, for example, J. F. Dyet, A. A. Nicholson, and D. F. E. Ettles, Vascular imaging and intervention in peripheral arteries in the diabetic patient, Diabetes/Metabolism Research and Reviews, 16:S16-S22, 2001.
Peripheral angiography is performed to visualize the arteries away from the center of the body. See, for example, S. E. Harms and D. P. Flamig, Magnetic resonance angiography, application to the peripheral circulation, Investigative Radiology, (27):S80-S83, December 1992 and J. S. Swan, T. J. Carroll, T. W. Kennell, D. M. Heisey, F. R. Korosec, R. Frayne, C. A. Mistretta, and T. M. Grist, Time resolved three-dimensional contrast-enhanced MR angiography of the peripheral vessels, Radiology, (225):43-52, 2002. One of the most common applications is to examine arteries that supply blood flow to the legs. See, for example, J. P. Carpenter, R. S. Owen, R. A. Baum, C. Cope, H. D. Berkowitz C. F. Barker, M. A. Golden, and L. J. Perloff, Magnetic resonance angiography of peripheral runoff vessels, Journal of Vascular Surgery, 16(6):807-815, December 1992; M. Goyen, H. H. Guick, J. F. Debatin, M. E. Ladd, J. Barkhausen, C. U. Herborn, S. Bosk, H. Kuehl, M. Schleputz, and S. G. Ruehm, Whole-body three-dimensional MR angiography with a rolling table platform: Initial clinical experience, Radiology, 224(1):270-277, 2002; Thomas M. Grist, MRA of the abdominal aorta and lower extremities, Journal of Magnetic Resonance Imaging, 11(1):32-43, January 2000; M. J. Koelemay, J. G. Lijmer, J. Stoker, D. A. Legemate, and P. M. Bossuyt, Magnetic resonance angiography for the evaluation of lower extremity arterial diseases: A meta-analysis, The Journal of the America1 Medical Association, (285):1338-1345, 2001 and O. C. Velazquez, R. A. Baum, and J. P. Carpenter, Magnetic resonance angiography of lower-extremity arterial disease, Surgery Clinics of North America, 4(78):519-537, August 1998. Examinations are also made of the abdominal region as well as the upper body. See, M. R. Prince, Gadolinium-enhanced MR aortography, Radiology, (191):166-164, 1994.
Physicians can now obtain angiograms covering the whole body for the complete vascular system examination. Due to the technical limitations of the MR systems, however, it is not possible to obtain the full body scan at once. It is only recently that the technology is approaching this goal with scanners that allow large field of view and volumes to be obtained in a single pass. However, there exists a great amount of data from previous procedures, when patients often had to be repositioned in between acquisitions. During the whole body imaging, a series of volumes is acquired and to enable diagnostic excellence in their interpretations, it is desired to visualize them jointly in one composed volume.
There is a considerable amount of work on the medical image registration topic dealing with different volume scales, rotations, affine (or higher order) transformations, deformations, multi modality and other complications. However, systems and methods for accomplishing the process of viewing a series of volumes in one composed volume automatically, without human intervention, are needed.